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2023 electrical short?

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3K views 28 replies 6 participants last post by  sjm9911 
#1 ·
2023P
It started acting up by slowing down and sometimes stopping. I took the cab off and found the e-unit was not screwed on, so I removed it from the bracket and sure enough the bracket mounting screw had come free. Then I posted to find out how to put it back together (thanks). Once together, I put it on the track and it went nowhere. The short indicator light lit on the transformer.
I took it apart again and found a yellow wire broke off from somewhere. I guessed it went to the collector and since I don't have yellow wire I soldered a black piece from a connection on the collector to e-unit. I tried to follow the wiring on the 2023 diagram.
The motor runs if you jump from the collector roller to the motor directly and the e-unit cycles if powered separately, but when everything is back together something is shorting out. I checked all the wiring for bare spots and tried to make sure all the wiring is as shown in the diagram. Now I don't know what to try next. I'm stumped and could use some pics of 2023 wiring. The diagrams help but pictures are easier for me to understand.
I need to make sure the collector is wired correctly.
I'd appreciate any help so I can get back to enjoying my trains.
thanks,
Newtown Joe
 
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#3 ·
2923 electrical short

Do you mean that flat insulator that sits on the top of the roller assembly? It is held on by a few tiny studs? I saw that and left it alone because it looked like it might break if I removed it so I just cleaned up some oil on.
Thanks for the help but I think there is something else wrong.
 
#4 ·
Sounds like that is not the problem. I dont have any pics right now but I was just wiring mine last night so I will see if I can help. From the rollers there should be one red wire from the center of the pick up to the side of the e-unit with the group of black wires. There should also be a black wire that goes from the sliding shoe to the front coupler. The yellow wire would run from the motor to the bottom fingers on the e-unit.
 
#8 ·
2023 electrical short

The yellow wire is correct as you describe.
I went from the collector underneath to the motor and then the e-unit and both made the engine run. Put it on the track and it shorts. I found a loose yellow wire and think maybe a previous owner replaced the red wire to the collector with this yellow wire so I redid it with a black wire because that's what I had. I put it from the collector to the e-unit where three other wires connect. Part of the problem with working on these old engines is you never know what the previous owners did and if they changed wire color. This diesel ran really well since I got it,:dunno::dunno: but something changed. I'm starting to suspect the e-unit. Although it cycles, I noticed that when it's set on the contact it shorts but when I move it away it works.
The lever always seemed to be loose and would move on its own once in a while.
These are the clues but I'm not going to change the e-unit until I'm sure it's defective.
 
#10 · (Edited)
If the lever to the e unit is loose it is not making a good connection to the positions, it won't cycle right.
But I don't think that would make it short out.

sounds like there is a wire hooked up wrong somewhere.
 
#13 ·
2023 electrical problem

To get back to the beginning it started by hesitating and stopping on occasion. I discovered that the e-unit mounting bracket screw managed to unscrew and the e-unit was free. I remounted it and then it stopped running on the track. I didn't alter any wiring up to this point. Then I noticed a yellow wire that was disconnected. I removed the collector and only saw one wire attached so I guessed that the yellow wire came off of the contact. I know that wire is supposed to be red but there was no red wire at all.
So I guess I need to study the wiring again and make sure everything is correct. I do see in the diagram that there is a insulating washers and spacer that go on with the collector screws. I only have one washer on one of the screws. How important are these to preventing a short?

http://pictures.olsenstoy.com/cd/locos\loc2023e.pdf
 
#14 ·
Try this, Lay the engine on it's side, jump your u terminal from the transformer to the pick up roller. Then jump the a terminal to the front wheel, the motor should run. Then try jumping the a terminal to a rear wheel, if it shorts there then the problem lies with the pick-up and is probably related to the insulators. remove the screw that is does not have the washer and try again. maybe you can isolate the short this way?
 
#19 · (Edited)
2023 electrical probelm

Well, here's some pics of my bad boy. Note the one with the red jump wire from the contactor to the motor. The wheels are spinning at top speed.
 

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#20 ·
In looking at the diagrams and your pics I've found one thing. There may not be a red wire, the wire from the pick-up. The wire from the pick-up goes to the circled area. If you connected the yellow wire to the pick-up, you may have created a short there. Hopefully the pic will help you out. Check this thread http://www.modeltrainforum.com/showthread.php?t=3040 T-man did an e-unit repair, so it should help.



Carl
 
#21 ·
Diagram Drawing Plan Technical drawing Font


Text Diagram Drawing
Ok, some pictures of the wiring diagram. Don't know if it's the one you have allready. Also, I'm not great with this electronic stuff so if you're missing the insulated spacer/washer on the collector plate I'm sure they insulate something. It looks as if you tryed to use some gasket maker in there? That might work, I really don't know. Don't let Kwikster s new title fool you, those paper shuffles have a lot of knowledge! (congratulations on your new title!)
 
#22 ·
2023 electrical problem

I have a hunch the wire I soldered to the collector is the problem. I think at first a wire came loose and caused an intermittent problem, then I incorrectly soldered a replacement and now the problem is consistent. I'll do some experimentation tonight. Thanks for the help but this is a trial and error situation, so I just need to keep trying different things. The fact that a direct connection to the motor works tells me when it's on the track the current is going through the e-unit in the wrong direction and shorting out. I'll study the diagrams again.
 
#23 ·
Maybe the solder just ran out and connected it to something it shouldn't be connected to? I don't know but I'll relook at everything tomorrow when I get a minute. Sometimes it's good to put a project aside for a day or two and get a different perspective on the problem. I can't tell you how many times I did that and the problem was something simple.
 
#24 ·
2023 electrical problem

Well, I re-soldered the wire to the collector and it ran! but only in reverse. Then it would stop and go and sometimes go after a gentle tap on the cab. Then back to shorting out.
I think the e-unit is defective or the wiring to it is shorting out. I'm still baffled by this and not sure what is causing all this eradicate behavior. When it ran it was fast and normal and sometimes it would stop, go into in neutral and not short. That lever on the e-unit seems to be loose and changes position with the motion of the train.
Anyway, it was nice to see it running, albeit for a short time.
 
#25 ·
Glad to hear you made progress. The lever being loose can be easily fixed. Check this thread for more very helpful information http://www.modeltrainforum.com/showthread.php?t=3040

T-man tightened the lever using a piece from a broken tape measure, TJ used a razor knife blade cut with a Dremel.

Carl
 
#26 ·
Joe

I'm sitting here gnashing my teeth knowing that with your
loco in hand and my trusty little
cheapo multimeter from Harbor Freight I'd solve your problem in
a few minutes.

Do you have a meter? Harbor Freight ads this week offered one free.

With the wiring diagram in hand make certain your loco is
actually wired as shown.

Use the meter first to find the short
circuit. (set the meter to ohms; turn it on) Touch the probes together.
A short should go full scale.
As you continue the test you'll note a lesser reading
which the is resistance of the motor & E unit. Ignore that. If the
readings are similar change the Resistance setting on the meter.

There should be no connection from the center rail rollers to
any wheel. Verify that with a probe on a roller and the other
touching each wheel. At each wheel Jiggle the roller plates to
determine if it is loose and shorting. A loose bolt or tab could do that.
From your text that could be the shorting problem.

If not, the loose lever could be shorting. Secure it in some way.
It has one function. To disconnect the E unit solenoid coil so it
will not change direction.

The E unit gets it's 'ground' from the frame thru
the lever tab. If that contact is
intermittent it can change direction at will. Any loss of current
to the E unit will cause it to ratchet and change direction

Check those points. That should solve the shorting and
direction changes. Beyond that it's going to take tracing the
current path from the rollers to the motor, thru the E unit. For
this I would set the meter to AC volts and with loco on it's side
but secure, attach wires from the transformer to the rollers and to the frame.
Turn up a 'slow' voltage. Use the meter probes where you have made
the connections and note the voltage. Secure one probe to the frame.
With the wiring diagram, follow the patch of the circuit by touching the
other probe at each connection point right thru to the motor.

Interrupt the voltage to the loco to operate the E unit. Then repeat
the trace.

Somewhere in there you are going to find a lack of continuity to
the motor. Else it would run.

Others has brought it up, but have you cleaned the internal
contacts of the E Unit? Make sure the wipers contact the
revolving drums. The E unit solenoid should ratchet the drums
each time current is interrupted.

There is no complex electronics in your loco. It is straightforward
simple DC. It may take slogging thru the connections to find
the bad boy but it is solvable.

Get back to us with what you find.

Don
 
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